A shock absorber used in a suspension apparatus that supports a vehicle wheel of a vehicle typically includes a cylinder, a piston rod that enters and exits the cylinder, a piston held by the piston rod so as to move through the cylinder in an axial direction, an expansion side chamber and a contraction side chamber that are formed in the cylinder, defined by the piston, and filled with a working fluid, a passage connecting the expansion side chamber and the contraction side chamber, and a valve body provided in the passage. When the shock absorber expands and contracts, one of the chambers contracts and the other chamber expands such that the working fluid in the contracting chamber moves into the expanding chamber through the passage. As a result, the shock absorber generates damping force from resistance in the valve body.
In a shock absorber disclosed in JP2012-47341A, for example, two valve bodies, namely a leaf valve on which an initial load is exerted by a biasing spring and a needle valve that forms an orifice, are provided in parallel midway in a passage that connects an expansion side chamber to a contraction side chamber. When a piston speed is in a low speed region, the shock absorber generates damping force from resistance in the orifice formed by the needle valve, and when the piston speed increases so as to reach a medium/high speed region, the shock absorber generates damping force from resistance in the leaf valve. A first adjuster for adjusting an opening amount of the needle valve and a second adjuster for adjusting a valve opening pressure of the leaf valve are attached to a cap member that holds a piston rod. As a result, the two types of damping force generated respectively when the piston speed is in the low speed region and when the piston speed is in the medium/high speed region can be adjusted.